In two previous pieces I raised the topic of bringing extinct species back to life, making such things as Tasmanian Tigers and Gastric Brooding Frogs un-extinct through DNA sequencing and clever artificial fertilisation techniques. Outside of any ethical and difficulty questions there were a few points that I thought were worth thinking about.
The first was that animals are not just a single species but rather complex communities of living organisms and bringing back to life the extinct animal using re-sequenced DNA therefore would only bring back the host and not the entire organism.
The second was that if a species has been extinct for some time there will have been a general rearrangement of the remaining competitive species and so the niche previously occupied by the now extinct animal will have become occupied by an alternative animal.
My third point considers at one point an animal is extinct. Clearly if one is still alive then it is not technically extinct but, unless it is an hermaphrodite, it is functionally extinct. For a species to survive there needs to be a breeding population that is sustainable. Can a species that only exists in zoos be counted as thriving?
So bringing back one animal would be no good. There would have to be more than one, probably several more and of mixed gender to make a breeding programme realistic. And here in lies the rub. In order to do this there are two real choices for the budding revivalist:
The first is to take DNA from multiple samples of the extinct species but this is difficult as very few copies of extinct animals exist in a form where their DNA can be extracted.
The second is to use a single animal’s DNA and clone that to create multiple organisms. Doing this would create exact copies which would obviously raise the problem of gender difference. Bringing back animals from one example would also have a very limited gene pool ( a gene pool of one).
All species that are thriving and, therefore not extinct, have complex gene pools that allow for variation within the species so I argue that a single representative would set off on a different evolutionary route and end up being a different species altogether.
I heard that it had been finally confirmed, earlier this week, that it will not be possible to bring the dinosaurs back to life. Scientist had been investigating flies trapped in amber from the same time period and were unable to find, let alone extract any DNA at all. This is the end of our Jurassic Park dream.
There are probably many more things to consider in what is an absolutely fascinating subject but I’d best stop here.
Thoughts from a Guerrilla Worker 